def reverse_in_place(arr):
    i = 0
    j = len(arr) - 1

    while i != j and i < j:
        arr[i], arr[j] = arr[j], arr[i]
        i += 1
        j -= 1

    return arr


result = reverse_in_place([4, 12, 14, 16, 18])
print(result)
